buffer underflows encoding HD video to ntsc-dvd

Description

Summary of the bug: Since upgrading to v1.0.5 (and now 1.0.6) I've been getting hundreds of buffer underflows converting my HD video to DVD format, specifically NTSC format. I don't do anything special to the video to encode them and even video I've successfully encoded before are giving underflows when before they encoded cleanly.

I am not a n00b at building and compiling source, but I've never compiled ffmpeg before so I'm not sure if I'm missing something. I want to make sure that the problem is in ffmpeg and not in a compile option from the Fedora guys.

Please always start with ./configure && make then add external libraries if you need them.
Some of the configure options you used look broken (or at least useless) to me.

Could you elaborate if there is an issue with current git head? Or with 1.2? If not, I will close this ticket.
If it is really a regression, it could be fixed, but this would at least require a reproducible test case (that I so far do not see).